EWSR1 and myeloproliferative disorder: For example, Ewing sarcomas with EWSR1-ERG fusions can be detected with the ERG antibody (Wang et al, 2012), although this is not specific, as other neoplasms (including vascular tumours, ERG-related myeloproliferative disorders and prostatic adenocarcinomas) express ERG (Miettinen et al, 2011).